Radio / Spirit of America Radio 4

As anybody who lives within earshot of a burglar alarm will tell you, it doesn't take an actual burglar to set alarm bells ringing - a cat will do it, or a gust of wind. The fact that nothing is seriously wrong isn't much consolation when you have to live with the noise, though.

This was, roughly speaking, the trouble with the opening programme of Spirit of America, six discussions of American history with prominent African-Americans: alarm bells rang a few times, and though nothing seemed to be missing when you checked, it still set your nerves on edge.

John Hope Franklin, a historian of slavery and the Civil War, was telling Caryl Phillips about the process of emancipation - his thesis being that Lincoln's proclamation had more importance as propaganda than for practical effect. At one point, Phillips suggested that the proclamation contained some measure of duplicity. "Well, I'll say what it said," Professor Franklin offered, "and you can reach your own conclusions [as to] how duplicitous it was. There was no question about the preliminary proclamation extending freedom to the slaves in those areas that were occupied by the Confederacy. It did not extend freedom in those areas that were occupied by the union. In other words, slaves were set free where they could not be free... and they were not set free in the areas where they could be set free."

"That seems pretty duplicitous to me," said Phillips. "You conclude it," chuckled Franklin. To be accurate, though, it was Franklin who had concluded it: what he had done was the equivalent of offering Phillips two and two and telling him to put it together, and then saying "Four? Well, that's your opinion, nothing to do with me." The answer is clearly going to be four; you just wonder if maybe there shouldn't have been a three instead of a two somewhere in the equation.

On the whole, the version of history Professor Franklin presented (in which, "by their own determination", slaves achieved de facto liberation, and the de jure kind slipped in afterwards) seemed more plausible than the old myth (in which Lincoln signed a piece of paper and everyone started singing). But it was also, clearly, a version designed to fit with modern ideas about empowerment and personal achievement; and it was hard to quell the suspicion that we were getting one side of the story. You wished that Phillips was readier to test Franklin's version harder; instead, he seemed mostly content to sit at his feet and absorb the lessons - which made not only the history but the conversation seem one-sided.

Alarm bells rang again during Trust, a sitcom set in an NHS trust hospital run by nice doctors, ruthless managers and, as tradition dictates, randy nurses. Wendy Lee's script had some very funny sequences, notably a Dutch auction for patients where Keith Allen's snarling surgical manager beats other hospitals to a terminal case by throwing in two days' tea and biscuits for visiting relatives. But it also smudged the lines of plausibility too carelessly, so that the "It could happen here" effect was lost. If NHS trusts have to be squeezed this heavily for jokes, you wonder if they can be as bad as all that.